The intensity of seismic signals measured in the course of seismic prospecting is dependent on the depth of beds and their physico-chemical properties, as well as on the conditions under which seismic waves are produced. The operator of a telemetering system is practically unable to adjust the equipment in accordance with seismic signal parameters, keeping in mind that the equipment is located at a distant site. This means that the dynamic range of a telemetering seismic signal recording system must be as broad as possible. The transmission of seismic signals over long communication channels must be carried out in the digital form so as to reduce the effects of noise and distortions on the results of measurements. At the same time the telemetering units of seismic signal recording equipment must be economical from the viewpoint of power input. This requirement applies both to battery and external power supply, and to meet it, today's telemetering equipment incorporates economical low-voltage circuits.
However, a lower supply voltage means a narrower dynamic range. In fact, each time the supply voltage is reduced two-fold, the dynamic range decreases by 6 db.